Machine for opening oysters



Sept. 25, 1928.

0. SCHENK MACHINE FOR OPENING OYSTBRS Filed Dec. 2''!- 1920 11 J T m I a g. I z o z O M a z I 51 M M y a z I. v 2 K I INVENTOR.

ATTORNEY f Fete-rated Sept. 25, 1.928.

entree staresteeazee i mea t a ta OTTO soHENK; or DAYTON, onro, essxenon. ro ARL. a. dimers AND CLARENCE N; '1 1 srnmrnn, BOTH or'na'rrroit, onto; 1

aoniitn ron'ornnriie orsrnns.

Application filed December 2'7, 1920; Serial No. 433,206.

enable oysters to be opened much more rapidly thanit is possiblelfor even the most skillful workman to open oysters by hand. An-

other object is to enable unskilled persons to open oysters; there a're'many hotels and res taurants where it: is impracticable toserve shell oysters. because they do not have enough of that business to warrant their keeping a skilled oyster opener. Another object of my invention is to provide means for opening oysters which practically eliminates the danger of bits of shell getting among the I opened oysters; oysters may be opened by attached to the frame 13 at 20. Thelever my method and with my machine without splintering the shell. Another object of my invention is to provide for opening oyster shells without injuring the oyster.

1 effect the above mentioned v and other objects, which will be referred to later, by

' the method which consists primarily in foreor knife'between ing a pointed instrument the shells at their hinge. The mouth of the shell. that is the end remote from-the hinge] is held against a fixed bearing'or abutmentv and the instrument is "forced between the shells at the hinge by pressure directed substantially towardthe mouth ofthe shell. A.

very slightseparation of the shells atthat point ruptures the hinge. As soon as the hinge is ruptured I relieve the pressure and move the mouth of the. shell to a lower point on the abutment. Then entering the knife once more at the hinge I drive it by aquick impulsive movement toward the abutment. The mouth of the shell is held at a point' onthe abutment low enough so'that as the knife enters between the shells it slides along the inner surface of the upper halfot the shell and severs the shell closing muscle from'the upper half.

Referring to the accompanying drawings,

Figure 1 is a side elevation of a machine whereby my method of opening oysters may be put into effect. Y

Figure 2 is a plan of the machine. Figure 3 is a view showing the operation of cuttingthe oyster from the lower half of the shell after thenpper has'been removed.

- Figure 4 sh ows'the first step of my method which consists in. rupturing the hinge of the shell Figure 5 shows the second step; that of severing the muscle from the upper shell.

In the present structure the base 10 of the machine is made of wood and at one end of the base a vertical wall 11' is attached by suitable ironangle plates 12, which wall I will hereinafter refer to astheabutment. Mounted on the'base lOisa frame 13, in the upper portion of which a bar 14 is mounted to 'slideis moved longitudinally'by means of a lever r This lever isattached to a sort offioating fulcrum; that is,.at 17 it is pivotally attachedtoa link 18i which link is pivotally atta'ched'to a second link 19,' the latter being is pivotally attachedtol the bar 14 at 21, and this point of attachmentis made adjustable and the bar with extraholes 23, for the recep- .by providing the lever with eXtraholes 22 it tion .of pivotalmember 21. A sp'ringjQl normally draws the lever;16.toward the abut V ment. If desired this spring may be attached differently; That is. it may be attached from a point 25 on the frame 18 to the pivoted member 21. In order to balance thestrain, two springs are provided, which will be seen by-referri'ng to Figure 2. Mounted on the knife 27. The machine maybe secured to a base 10 is a block 26 which carries a stationary table or provided with legs or some form of pedestal; So far as my present invention is concerned this is immaterial. I

The operator stands atjA, facing the machine; Taking an oyster in his hand withthe' hinge adjacent to his index finger, and having V pushed the lever 16 from him, he places the hinge ofthe shell against the point of the matcly parallel withtheline ofmovement of the knife he draws the lever-toward him until knife 15. Then holding the shell approxipressure on the leverhe forces the point of the knife between the she'lls,,th us rupturing lowers 'the'mouthof-the shell and draws the the hinge, but he does not force the point far I lever toward him again, bringing the'mouth f Y of the shell against the abutment, as in Figure 5. -He thengives the lever aquick jerk and removes his from it, allowing the sprin its "tact; with :theloysters:

24 to move" the lever. By reference toFigure 5 it will be seen that with the mouth of the shell held loW on the abutme11t,ltlie knife upon entering the shell quickly impinges on V 5 theinner surface of the upper half and lifts it to a position suggested by dotted lines.

sliding along the innerjsurface of the shell in this Way the knife severs the muscle from the shell neatly and without the slightest injury to the oyster; The spring supplements the start given the handle by the operator, s md ba cke d by the momentum of the handle, which is heavy, the movement of the'knizte has animpulsive quality that is very effective i'n severing the muscle from the shell.v The effeot may be likened to that of a butchers cleaver, as compared to cutting by steady pressure on a knife. ALS soon as the muscle r is severedfroxn the shell the operator takes the 'l'o'wer half of the shell and the oyster f beneath the knife, leaving t 1 1 7 half on top'of the knife. The upper ha f 0f theshell, in fact, seldom remains on the knife,

but usually falls off of it. WVith the lower half of'the shell still: in the same position in his hand, the operator passes the shell beneath the knife 27, causing the knife to pass between the oyster and the'shell, thus severing the lower muscle.- i

" kWhile, as I have previously stated, oysters can be opened by my method and with the machine described Without previous-experienee muchfaster than the most slzillfulworkman canopenthemby hand, the operator of mymachinevery quickly acquires a skill and dexterity in its operation which enables him 'to open' oysters With remarkable rapidity.

The machine-and method are both devised with" the View of eliminating every'unneces-u sary motion. The oysters opened in this Way are free from'bits of shelland on thewhole are cl'eaner than hand-openedoysters. The

"operator is farther removed fromthe oysters than'when opening them. by: hand, and there is lessprobability of his breath' c-oming'in con- *a- In thepresent machine the and'abut- V i nlient arewood, but it is obvious that they may 1 {be made of metal- The Wood abutmenthas 50 certain advantages, however; the oyster shell .is le'ss likely to slip on the WOOdl espeeiallyin the seeondoperat on, as inF-iguro 5, than if the abutment were of metal. Where the 7 "abutment is. made :of metal itrmay be covered with'wood .or some other non-metallic: material; or itmay be roughenedsomewhatlike the surface of. a file.v it is'd'esirable, however,'to

be able to place thc'shell against any part of the abutment, as the angle at Which the oyster is held during. the second operation maybe varied somewhat according to the contour of the shell; 7

the operator quickly acquires a certain skill.

This isrone of the points wherein There is considerable variation in the shape of oyster shells and the operator quickly acquires the knack of holding the shell at. an angleapproprlate to its own characteristics scribed, as-thereis more or lessvariation in the Work of different operators. The important pointinimy method is'to enter the knife at the hinge and rupture'the hinge, then to change the-direction of action of thekniie so that It? will sever the muscle from the upper 7 half of: the shelli'vithout injuring theoyster. The details of action whereby these main ob ects are accomplished-are more or. less optionalWith the operator. Nor isit tobeas- 1'. A machine for openingoysters, compris- 111g a movable kmi'e, an abutment against which to hold an oyster Whileits shell is opened'with the kni-fe, a; sprmg constantly tendingtomove'the'knifo toward the abutment, and a manual operating member Whereby to Inovethe-knite to and fro with refer ence to theabutment, saith member having a largerange ofmovement relative tothe distance moved by the knife,,and being heavy enough to enable momentunr imparted. to it by the'operator to supplement the actionlo'f the springin moving said member toward the abutment. V g

'2; A: machine for= '0pening oysters, comprisinga base, an abutment carried thereby, .a knife mounted onsa-idbas-e; and adapted to movelongi'tudinally to and fro Witlureferenee to the abutment, a, lever 'ful'criunett on the base :for moving the knife and; a spring" connected to andadapted to move the; knife toward the.abutment,

oiTosoi-rsiui;

and he soon ets to doing'this subconsciously.

It is not to be understood that my invention I is limited tmthe particular movements de- 170 

